Use document style ux when print conversations to pdf

Inspired by my previous turnstyle ux explorations.

But basically user message becomes section title and khoj message
becomes section body with the timestamp being used a section title,
body divider.

src/interface/web/app/components/chatMessage/chatMessage.tsx

@@ -713,6 +713,7 @@ const ChatMessage = forwardRef<HTMLDivElement, ChatMessageProps>((props, ref) =>
             className={constructClasses(props.chatMessage)}
             onMouseLeave={(event) => setIsHovering(false)}
             onMouseEnter={(event) => setIsHovering(true)}
+            data-created={formatDate(props.chatMessage.created)}
         >
             <div className={chatMessageWrapperClasses(props.chatMessage)}>
                 {props.chatMessage.queryFiles && props.chatMessage.queryFiles.length > 0 && (